1. Field of the Invention
The present invention relates to control circuits, and particularly to a memory voltage control circuit.
2. Description of Related Art
Currently, a typical personal computer is comprised of a motherboard, interface cards, and peripheral accessories. The motherboard is the heart of the personal computer. In addition to the central processing unit (CPU), the chip set and slots for installing the interface cards, the motherboard also includes slots for installing memory modules.
Due to constant changes in the computer industry, memories that are typically used in computers have changed from DDR2 (Double Data Ram II) to higher speed memory chips such as DDR3 (Double Data Ram III).
Because DDR2s are cheaper than DDR3s, DDR2s are still in demand in the market to be used on the main board. The difference in operating DDR2 versus DDR3 includes the following: DDR2 utilizes 1.8V VDD and 0.9V VTT, while DDR3 utilizes 1.5V VDD and 0.75V VTT. Currently, no motherboard is compatible with both DDR3 and DDR2.
What is desired, therefore, is a memory voltage control circuit that can simultaneously support different types of computer memory.